Dinuclear neodymium and lanthanum bis(2,6-diisopropylphenyl) phosphate complexes bearing a hydroxide ligand: catalytic activity of the Nd complex in 1,3-diene polymerization.

Title Dinuclear neodymium and lanthanum bis(2,6-diisopropylphenyl) phosphate complexes bearing a hydroxide ligand: catalytic activity of the Nd complex in 1,3-diene polymerization.
Authors M.E. Minyaev; S.'yaA. Korchagina; A.N. Tavtorkin; A.V. Churakov; I.E. Nifant'ev
Journal Acta Crystallogr C Struct Chem
DOI 10.1107/S2053229618006666
Abstract

The reactions of K[(2,6-PrCH-O)POO] either with LaCl(HO) or with Nd(NO)(HO) in a 3:1 molar ratio, followed by vacuum drying and recrystallization from alkanes, have led to the formation of diaquapentakis[bis(2,6-diisopropylphenyl) phosphato]-?-hydroxido-dilanthanum hexane disolvate, [La(CHOP)(OH)(HO)]·2CH, (1)·2(hexane), and tetraaquatetrakis[bis(2,6-diisopropylphenyl) phosphato]-?-hydroxido-dineodymium bis(2,6-diisopropylphenyl) phosphate heptane disolvate, [Nd(CHOP)(OH)(HO)]·2CH, (2)·2(heptane). The compounds crystalize in the P2/n and P-1 space groups, respectively. The diaryl-substituted organophosphate ligand exhibits three different coordination modes, viz. ?O,O'-terminal [in (1) and (2)], ?O-terminal [in (1)] and ?-?O:?O'-bridging [in (1) and (2)]. Binuclear structures (1) and (2) are similar and have the same unique Ln(?-OH)(?-OPO) core. The structure of (2) consists of an [Nd{(2,6-PrCH-O)POO}(OH)(HO)] cation and a [(2,6-PrCH-O)POO] anion, which are bound via four intermolecular O-H...O hydrogen bonds. The molecular structure of (1) displays two O-H...O hydrogen bonds between OH/HO ligands and a ?O-terminal organophosphate ligand, which resembles, to some extent, the `free' [(2,6-PrCH-O)POO] anion in (2). NMR studies have shown that the formation of (1) undoubtedly occurs due to intramolecular hydrolysis during vacuum drying of the aqueous La tris(phosphate) complex. Catalytic experiments have demonstrated that the presence of the coordinated hydroxide anion and water molecules in precatalyst (2) substantially lowered the catalytic activity of the system prepared from (2) in butadiene and isoprene polymerization compared to the catalytic system based on the neodymium tris[bis(2,6-diisopropylphenyl) phosphate] complex, which contains neither OH nor HO ligands.

Citation M.E. Minyaev; S.'yaA. Korchagina; A.N. Tavtorkin; A.V. Churakov; I.E. Nifant'ev.Dinuclear neodymium and lanthanum bis(2,6-diisopropylphenyl) phosphate complexes bearing a hydroxide ligand: catalytic activity of the Nd complex in 1,3-diene polymerization.. Acta Crystallogr C Struct Chem. 2018;74(Pt 6):673682. doi:10.1107/S2053229618006666

Related Elements

Lanthanum

See more Lanthanum products. Lanthanum (atomic symbol: La, atomic number: 57) is a Block F, Group 3, Period 6 element with an atomic weight of 138.90547. Lanthanum Bohr ModelThe number of electrons in each of lanthanum's shells is [2, 8, 18, 18, 9, 2] and its electron configuration is [Xe] 5d1 6s2. The lanthanum atom has a radius of 187 pm and a Van der Waals radius of 240 pm. Lanthanum was first discovered by Carl Mosander in 1838. In its elemental form, lanthanum has a silvery white appearance.Elemental Lanthanum It is a soft, malleable, and ductile metal that oxidizes easily in air. Lanthanum is the first element in the rare earth or lanthanide series. It is the model for all the other trivalent rare earths and it is the second most abundant of the rare earths after cerium. Lanthanum is found in minerals such as monazite and bastnasite. The name lanthanum originates from the Greek word Lanthaneia, which means 'to lie hidden'.

Neodymium

See more Neodymium products. Neodymium (atomic symbol: Nd, atomic number: 60)is a Block F, Group 3, Period 6 element with an atomic weight of 144.242. Neodymium Bohr ModelThe number of electrons in each of Neodymium's shells is 2, 8, 18, 22, 8, 2 and its electron configuration is [Xe] 4f4 6s2. The neodymium atom has a radius of 181 pm and a Van der Waals radius of 229 pm. Neodymium was first discovered by Carl Aer von Welsbach in 1885. In its elemental form, neodymium has a silvery-white appearance. Neodymium is the most abundant of the rare earths after cerium and lanthanum. Neodymium is found in monazite and bastnäsite ores. It is used to make high-strength neodymium magnets and laser crystal substances like neodymium-doped yttrium aluminum garnet (also known as Nd:YAG). The name originates from the Greek words neos didymos, meaning new twin.

Phosphorus

Phosphorus Bohr ModelSee more Phosphorus products. Phosphorus (atomic symbol: P, atomic number: 15) is a Block P, Group 15, Period 3 element. The number of electrons in each of Phosphorus's shells is 2, 8, 5 and its electronic configuration is [Ne] 3s2 3p3. The phosphorus atom has a radius of 110.5.pm and its Van der Waals radius is 180.pm. Phosphorus is a highly-reactive non-metallic element (sometimes considered a metalloid) with two primary allotropes, white phosphorus and red phosphorus its black flaky appearance is similar to graphitic carbon. Compound forms of phosphorus include phosphates and phosphides. Phosphorous was first recognized as an element by Hennig Brand in 1669 its name (phosphorus mirabilis, or "bearer of light") was inspired from the brilliant glow emitted by its distillation.

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